The correct answer is A. Potassium-argon dating and half-life isotopes
Explanation:
Potassium-argon dating and half-life of an isotope is the only method to determine the ancient archaeological objects beneath the earth's surface.
According to geologists the age of rocks dates back to 4 billion years. These facts are based on the radioactive isotopes of potassium (K-40). This isotope, after its half-life, decays into argon gas (Ar-40).
The comparison of the amount of the isotopes K-40 to Ar-40 gives the information about the time period the rock has formed. This method is quite useful for paleoanthropologists and archaeologists to study human evolution.
Option A, Potassium-argon dating and half-life isotopes
Explanation:
Dating helps in determining the age of old rocks.The age of continental crust is determined by calculating the final weight of rock as compared their initials weight.
The formula for determining the age is as follows -
Where N is the final weight of the radioactive substance with in the continental crust.
is the initial weight of the radioactive substance with in the continental crust.
Mutualism is the interaction between two or more organisms where both organisms can benefit from the interaction. ... Parasitism is the interaction between two species where only one benefits from the other organism and the other is harmed in return.
The difference is in the location. If the rain forest is close to the equator, it is considered tropical. If the rain forest is farther away from the equator (between the Arctic Circle and the Tropic of Cancer or the Antarctic Circle and the Tropic of Capricorn) then the forest is considered to temperate.